Comments on: Through a Lens Darkly

By: Clifford

Clifford — Fri, 09 Mar 2007 02:55:10 +0000

You are getting more mature Jeff. Others just give up, and never get to the point you just described. This is part of what colloquia are for….

I’m pleased to hear this.

Cheers,

-cvj

By: Jeff Nuttall

Jeff Nuttall — Fri, 09 Mar 2007 02:33:54 +0000

That was an interesting talk. I wasn’t able to go to any of the colloquia last semester, because I was teaching an evening class at a community college, but this is the third one I’ve been to so far this semester, and I’m feeling better about my ability to actually understand the talks. Last year I was feeling kind of frustrated about the colloquia because it seemed they were always way over my head; I could only grasp a few threads of what the speaker was saying, and the rest was gibberish. So far in the colloquia I’ve attended this semester, I haven’t had that problem; I’ve been able to follow the concepts in the talks pretty easily. I’m not sure why the difference; certainly I don’t think my general knowledge of physics has increased that much over the last year…

By: Clifford

Clifford — Thu, 08 Mar 2007 23:18:44 +0000

Hi Katie,

Thanks!

See the “related links” at the end of this post for posts I did on the Bullet Cluster.

-cvj

By: Katie

Katie — Thu, 08 Mar 2007 23:08:06 +0000

This was really a great talk – well described and illustrated beatifully. I particularly enjoyed the example of the Bullet cluster, differentiating the effects (or lack thereof) of a collision on dark matter and baryonic matter. Quite illuminating!

By: Clifford

Clifford — Wed, 07 Mar 2007 15:18:19 +0000

Of course, you’re absolutely right, and I do know that distinction! I’m not really sure why that term crept into my mind at all yesterday while writing the post. I must be going senile… I’ve changed it in the post. Thanks.

-cvj

By: mollishka

mollishka — Wed, 07 Mar 2007 13:44:27 +0000

Just a point of terminology: this is weak lensing, not microlensing. Microlensing is the term that’s used for what’s done by stars, such as in our own galaxy for planet detection (and is mainly a change in brightness), but weak lensing is the term that used for the small percent-level shape distortions of galaxies by intervening matter.